Just because you are non-profit does not mean you cannot license the IP that you own. In the case of a university, this income goes back into education. All research universities around the world patent and license their technology. There is a huge difference between aggregators of IP (trolls) that have no interest in commercializing the technology, and inventors and their institutions. Don't worry, even the US Congress has had trouble understanding why universities need to be able to own the IP they invent, and be able license that technology. So you are in good company (ha!).

You need to better understand the definition of patent troll. Individual inventors and inventive institutions like universities are not considered trolls. Companies that are NPEs and who buy up patents primarily for the purpose of making money via lawsuits are patent trolls. Intellectual Ventures is an outstanding example.

But the result is the same - someone with a patent not producing anything sues people who are supposedly using it for commercial purposes. Using your definition of patent troll if the exact same patents were sold to IV and they instead sued OVT, that is "bad", but when the university does it that is "okay".

Under the 1980 Bayh-Dole Act, IP developed by universities under US federal funding can be retained by the universities. Prior to that act, IP belonged to the federal government but the government did a very poor job of enabling the commercialization of that technology.